When to Plant Shiso in Marengo County, AL
May in the garden — Marengo County, Alabama
We've pulled the most time-sensitive tasks for Marengo County, Alabama this May and put them front and centre. Tackle them in order.
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Sow shiso in trays indoors
A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.
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Harvest shiso as they ripen
If you can't use it all right away, check the food-preservation section of your planner.
Looking ahead to June
- First harvests: shiso
Shiso (perilla) is a fragrant Japanese herb with large, ruffled leaves in green or purple varieties. It has a unique flavor combining mint, basil, and anise.
Marengo County, Alabama is in USDA Zone 8b. The average last spring frost is March 13 and the first fall frost is November 13, giving you a growing season of approximately 245 days.
At an elevation of 453 feet, Marengo County receives approximately 59.8 inches of rainfall annually with predominantly clay loam soil. Summer highs average 90°F, providing good warmth for Shiso during the growing season. Clay soil retains moisture well for Shiso, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Shiso root diseases.
Marengo County Soil Profile
Soil Type
Clay Loam
Soil pH
5.2-6.7
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Marengo County
How your county's soil matches Shiso's growing requirements.
Soil pH
Your soil pH (5.2–6.7) overlaps with Shiso's range (5.5–7.0), though not a perfect match.
Soil Texture
The clay loam soil in Marengo County is excellent for Shiso — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Shiso.
How to Plant Shiso
Succession Planting Shiso
Sow every 5.7 weeks. Last sowing by Sep 04 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Shiso
Shiso needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Shiso Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.5" | 0" | ❄️ Dormant |
| Feb | — | 5" | 0" | ❄️ Dormant |
| Mar | 4.3" | 5.3" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5.8" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5.7" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 6.1" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Dec | — | 4.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Marengo County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Shiso Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Shiso Planting Timeline — Marengo County, AL
Shiso Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 23 | Jan 23 – Feb 6 |
| Transplant Outdoors | March 27 | Mar 27 – Apr 10 |
| Direct Sow | March 20 | Mar 20 – Apr 10 |
| Harvest | May 22 | May 22 – Jul 17 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors |
| March | Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
245 days in Marengo County
Growing Tips for Shiso in Marengo County
Direct sow Shiso outdoors after March 13 in Marengo County when soil has warmed and frost danger has passed.
With Marengo County's clay soil (30% clay), work in 3-4 inches of compost before planting Shiso. Avoid tilling when soil is wet to prevent compaction.
General growing tips
Direct sow after last frost or start indoors. Both green and red varieties are available. Pinch tips to encourage bushiness. Self-sows prolifically; deadhead to control.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Shiso in Other Locations
Frequently Asked Questions
When should I plant Shiso in Marengo County, AL?
Marengo County is in Zone 8b with an average last frost of March 13. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.
What planting zone is Marengo County, AL?
Marengo County, Alabama is in USDA Hardiness Zone 8b. The average last spring frost is March 13 and first fall frost is November 13.
Your Marengo County Garden Planner — Free
A 24-page printable planner built for Marengo County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.